Method of making carbon disulfid



one of various ways in I UNITED" STATES- PATENT OFFICE.

- nnmann'r u. now arm cnannns a.

,A CORPORATION OF MICHIGAN.

unrnon or Maxine cannon No Drawing.

county of Midland, and State of Michigan,

a new and useful 1m rove- .isulfid, of which thefollowing is a specification, the herein exp ained and the best'mode in which we have contemplated applying that principle, so as to ventions;

As is well known, used process for making have invented the old and generally carbon disulfid (CS is to pass sulfur vapor over cokeheated to a dull red heat, the two elements thereupon directly uniting, viz (1-1-8 CS It has also been proposed tomake such disulfid by heating pyrites (FeS,) or other suitable sulfid with carbon at a red heat, as

also to lead sulfur dioxid over red hot carbon. (See Bluchers M odern Industrial Chemistry, p. 139.) Neither of the last mentioned processes, however, have ever,so far as we are aware, gone into commercial use or even been successful in practice.

The object of the present invention is to provide a method for successfully using sulfur dioxid to react on the carbon, and to this end such invention then consists of the means hereinafter fully described and par ticularly pointed out in the claims, the following description setting forth in detail certain steps embodying theinvention, described steps constituting, however, but which the principle of the invention ma be used. I

It has been foun, that in order to continue the ieaction between sulfur dioxid and carbon, it is necessary to suppl additional heat because of the endothermic character of the reaction, and the difiicultyfof supplying such heat extraneously has 111111- tated against the success of the process. We have found, however,

initially brqu ht to a temperature (red hot in the case 0 coke) where the sulfur will combine therewith to form carbon disulfid, such temperature can be maintained by ineludin a certain, relatively small,'proportion of oxygen, 11. e. air, with such dioxid.

In order that rinciple of the invention being.

distinguish it from other insuch ' tain vegetable oils are that where carbonin the proper form is used. and suchcarbon other gases or vapor! the dioxid may be pure, as

V STROSACKER, OF MIDLAND, MICHIGAN, ASSIGNORS TO THE DOW CHEMICAL COMPANY,

OF MIDLAND, MICHIGAN,

DISULFID.

' Specification of Letters Patent. Patented Aug, 24, 1920. Application filed July 15, 1918. Serial No. 245,084. I

also to permit the more readily proportioning of the air mixed therewith, such dioxid is desirably made by reacting on a sulfite salt such as calcium sulfite with a suitable acid. The gas thus resulting, admixed with the proper amount of air as aforesaid, is thereupon led into a suitable chamber or retort, preferably in the form of a tumblin barrel having a refractory lining, in whic a body of coke has been previously placed and brought to a dull red heat. As alread indicated, the sulfur dioxid will react wit such coke to form the desired. carbon disulfid, some carbon monoxid beingalso formed at the same time, in accordance with the following equations or in other words, causes such portion to burn, producing additional carbon dioxid, with the giving off of heat, this reaction being of course exothermic. As a result the coke is maintained at the temperature requisite for the reaction with the sulfur dioxid and such reaction will continue until the coke is substantially all used u a The carbon disulfid vapor, together with the carbon dioxid that is formed, are continuously withdrawn from the retort, and their separation effected in any suitable way. Since, however, lowerlng the temperature, it is necessary to absorbit' from such it from the absorbent. For the latter cera heavy mineral oil may be used.

The use of our improved process is not limited to the particular spurge of sulfur .dioxid described above, but such dioxid ma source and mixed wit so long as these are of a neutral character due allowance being made in such case for the additional heat be derived from any that may be absorbed thereb thus making itional amount it necessary to supply an ad the disulfid, being mixed. with gases, cannot be condensed by simply gases and then distil' preferable, although of oxygen with the sulfur dioxid. The advantage in utilizing the sulfur compound in gaseous form rather than the sulfur itself, which requires to be either liquefied or 'volatilized, should be at once apparent. At

the same time the process is rendered substantially continuous, requiring to be interrupted only in' order to charge the retort with a fresh quantity of coke.

Other modes of applying the principle of' our invention may be employed instead of the one explained, change being made as regards the process herein disclosed, providing the step or steps stated by any one of the following claims or the equivalent of such step or steps be employed.

We therefore particularly point out and distinctly claim as our invention I 1. T he method of making carbon disulfid which. consists in bringing sulfur dioxid in contact with heated coke, and admixing sufficient oxygen with such dioxid to maintain such coke at the requisite temperature.

2. The method of making carbon disulfid which consists in passing sulfur dioxid over coke at a red heat, and admixing sufiicient air with such dioxiil to maintain such coke at the requisite temperature.

3 The method of making carbon disulfid which consists in placing a charge of coke ina suitable rotary drum, bringing the same to a red heat, passingsulfur dioxid through such coke as such drum rotates,'and admixing suflicient air with such dioxid to maintain such coke at the requisite temperature.

4. The method of making carbon disulfid which consists in placing a charge of coke in a suitable rotary drum, bringing the same to a red heat, passing sulfur dioxid through such coke as such drum rotates, admixing sufiicient air With such dioxid to maintain such coke at the requisite temperature, and

then absorbing the resulting carbon disulfid from the accompanying gases in a suitable liquid medium. 7

5. The method of making carbon disulfid which consists in placing a charge of coke in a suitable rotaryfdrum, bringing the same .to a red heat, passing sulfur dioxid through such coke as such drum rotates, admixing suflicient air with such dioxid to maintain such coke at the requisite temperature, and then absorbing the resulting carbon disulfid from the accompanying gases in a heavy oil.

6. The method of making carbon disulfid which consists in placing a charge of coke in a suitable rotary drum, bringing the same to.a red heat, passing sulfur dloxid through such coke as such drum rotates, admixing such first reaction is maintained.

Signed by us, this 8th day of July, 1918.

HERBERTHMDOW. CHARLES J. 'sTRosAcKER.

bon, whereby the temperature requisite for 

